The research community knows very little about how coming into compliance with specific safety standards contributes to injury prevention. Only a few studies have addressed this issue even though a better understanding would help OSHA target its inspections better among establishment; and it would help the inspector decide which violations to focus on once they arrived at a worksite. The research proposed here will systematically examine the effects of compliance with particular standards by looking at changes in outcomes following the abatement of violations of those standards. In addition to examining the change in the number of injuries, the study will also look at their severity by using workers' compensation data to measure the financial losses that firms suffer as a result of the types of injuries that decline after specific standards are cited. The effectiveness of coming into compliance also depends upon its duration. We develop new methods to estimate the average duration of compliance with different standards. In addition, we provide what appear to be the first standard-specific estimates of the costs of compliance. To obtain our findings, we will use several different data sets. These include workers' compensation data from California and Pennsylvania as well as data from the national Survey of Occupational Injuries and Illnesses.